Continuous mining machine

ABSTRACT

A continuous mining machine has a self-propelled body portion with a conveyor extending longitudinally thereon to transport material dislodged by a forwardly extending drum member toward the rear of the mining machine. A gathering device is positioned below the drum member and has gathering arms to move the dislodged material onto the conveyor. A boom member is pivotally connected to the mining machine body portion and extends forwardly therefrom. A drum member having peripherally extending cutting elements is rotatably secured to the boom member and extends transversely in front of the mining machine. In one embodiment the drum member has a center section, a pair of intermediate sections positioned on the outboard sides of the center section, and a pair of end sections extending outwardly from the intermediate sections. Axial shaft members are secured at one end to the drum member center section and are telescopically positioned in a tubular member secured to the end sections. Another embodiment has a pair of intermediate sections positioned adjacent each other and a pair of end sections extending outwardly from the intermediate sections. An axial shaft member telescopically supports the intermediate sections. The boom member has a pair of arm members arranged to move laterally and extend the drum member to a dimension greater than the width of the mining machine. In one embodiment the center section and intermediate sections have opposed end walls that are nonperpendicular to the longitudinal axis of the drum member so that the drum member in its extended position has portions of the center section and the intermediate sections in overlapping relation. In the other embodiment the intermediate sections have opposed walls nonperpendicular to the longitudinal axis so that the drum member in its extended position has portions of the intermediate sections in overlapping relation. With this arrangement, the cutter elements on the sections of the drum member in an extended position of the drum member dislodge material along the entire length of the extended drum member. A further embodiment of the drum member includes an axial, mating tongue and groove arrangement between the ends of the center section and intermediate sections. The drum member sections in an extended position have the cutter elements on the tongue portions of the center section and intermediate sections in overlapping relation so that the extended drum member dislodges material along its length. A pair of motors are provided to drive the drum member through the telescopic shafting.

Waited States Patent [191 Karlovsky, Jr.

[111 3,73%,593 May 1,1973

[ CONTINUOUS MINING MACHINE [75] Inventor: Jerry Karlovsky, Jr., Nashville, 11].

[73] Assignee: National Mine Service Company,

Pittsburgh, Pa.

[22] Filed: June 21, 1971 [21] Appl. No.: 155,177

Related US. Application Data [63] Continuation-impart of Ser. No. 19,854, March 16,

1970, abandoned.

[52] US. Cl ..299/76, 299/80 [51] Int. Cl ..E21c 27/24 [58] Field of Search 299/75, 76, 80

[5 6] References Cited UNITED STATES PATENTS 3,3 l 8,638 5/l967 Kilbourne 299/80 X 3,317,245 5/1967 Arndt ..299/76 3,318,638 5/1967 Kilbourne.. ..299/80 X 3,317,245 5/1967 Arl'ldt ..299/76 Primary ExaminerErnest R. Purser At!0rneyStanley J. Price, Jr.

57 ABSTRACT l2 n lliiliii elements is rotatably secured to the boom member and extends transversely in front of the mining machine. In one embodiment the drum member has a center section, a pair of intermediate sections positioned on the outboard sides of the center section, and a pair of end sections extending outwardly from the intermediate sections. Axial shaft members are secured at one end to the drum member center section and are telescopically positioned in a tubular member secured to the end sections. Another embodiment has a pair of intermediate sections positioned adjacent each other and a pair of end sections extending outwardly from the intermediate sections. An axial shaft member telescopically supports the intermediate sections. The boom member has a pair of arm members arranged to move laterally and extend the drum member to a dimension greater than the width of the mining machine. In one embodiment the center section and intermediate sections have opposed end walls that are nonperpendicular to the longitudinal axis of the drum member so that the drum member in its extended position has portions of the center section and the intermediate sections in overlapping relation. in the other embodiment the intermediate sections have opposed walls nonperpendicular to the longitudinal axis so that the drum member in its extended position has portions of the intermediate sections in overlapping relation. With this arrangement, the cutter elements on the sections of the drum member 1n an exsections in overlapping relation so that the extended drum member dislodges material along its length. A pair of motors are provided to drive the drum member through the telescopic shafting.

18 Claims, 10 Drawing Figures mini:

PATENTEU 1 3 SHEET 1 [1F 4 PATENT H M' 1 1975 sum 2 OF 4 PATENTED RAY 1 I973 SHEET l4 UF 4 omw dfi im CONTINUOUS MINING MACHINE CROSS-REFERENCE TO RELATED APPLICATIONS This application is a continuation-in-part of copending application Ser. No. 19,854, filed'Mar. 16, 1970 and now abandoned.

BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a continuous mining machine and more particularly to a mining machine having a transversely positioned extendible drum-like dislodging device.

2. Description of the Prior Art Continuous mining machines with transverse cutting elements positioned in front of the mining machine are known. For example, in US. Pat. Nos. 2,695,164 and 3,310,247, a pair of boom members extend forwardly from the mining machine frame and have disc-like rotatable dislodging elements mounted thereon. To dislodge material from the face, the disc-like dislodging elements are rotated and moved both transversely and vertically. The amount of material dislodged in any given period of time is limited with this type of mining machine. Because of their disc-like configuration and their transverse dimension, the dislodging elements can not simultaneously dislodge material across the entire face. The mining machine is dependent upon the oscillating transverse movement of the dislodging elements to dislodge material across the entire face.

US. Pat. No. 3,305,273 discloses a mining machine having a transversely positioned drum member with end disc-like elements that are arranged to move laterally outwardly on the drum member to increase the length of the drum member. This arrangement requires servomechanisms positioned within the drug member to extend and retract the end elements. The servomechanisms limit the extensibility of the drum member and are subjected to substantial bending moments.

SUMMARY OF THE INVENTION This invention relates to a continuous mining machine that has an elongated body portion with a boom member extending forwardly therefrom. The boom member is pivotally connected to the mining machine body portion and rotatably supports a drum member on the front end. The drum member extends transversely to the longitudinal axis of the body portion and has a plurality of aligned sections. All of the sections are connected to each other for rotation as a unit and the end sections are movable toward and away from each other to extend and retract the drum member. Certain of the drum member sections inboard of said end sections have a configuration wherein the adjacent end portions are overlapped and maintain a continuous longitudinal cutting pattern along the length ofthe drug member when the drum member is in an extended position.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a top plan view of my improved continuous mining machine illustrating the drum member in an extended position.

FIG. 2 is a view in side elevation of the mining machine illustrated in FIG. 1 with the path followed by the drum member during the shear cycle shown in phantom lines.

FIG. 3 is a partial schematic view of the drug member illustrated in FIG. 1 in a retracted position and is taken along the line IIIIII in FIG. 1. The dash-dot lines in FIG. 3 indicate the cutting area of the cutting elements secured to the drum member.

FIG. 4 is a fragmentary plan view partially in section of the front portion of the mining machine of FIG. 1 illustrating the piston cylinder arrangement for extending and retracting the drum member and the planetary gear mechanism for rotating the drum member.

FIG. 5 is a fragmentary view in section ofa portion of the drum member illustrated in FIG. 1 in an extended position illustrating the telescopic shaft arrangement and the manner in which the various sections of the drug member are coupled together for rotation.

FIG. 6 is a view similar to FIG. 5 illustrating the drum member in a retracted position.

FIG. 7 is a view similar to FIG. 3 of another species ofa drum member.

FIG. 8 is a view in top plan similar to FIG. 1 of another embodiment of my improved continuous mining machine illustrating the drum member having a pair of adjacent intermediate sections. The drum member is illustrated in an extended position.

FIG. 9 is a fragmentary view in plan of the drum member illustrated in FIG. 8 with the drug member in a retracted position.

FIG. 10 is a view in side elevation of the mining machine embodiment illustrated in FIG. 8.

DESCRIPTION OF THE PREFERRED EMBODIMENTS crawler tracks 14. Hydraulic drive motors 16 are provided to propel the mining machine 10 on the endless crawler tracks 14 and advance the mining machine during the mining operation. An endless conveyor mechanism 18 is positioned in a longitudinal trough member 20 and conveys dislodged material therein from the front of the mining machine to an articulated rear discharge section 22. As illustrated in FIG. 2, a gathering device 24 extends forwardly from the body portion 12 and is arranged to gather the dislodged material and feed the dislodged material onto the conveyor trough 20 so that the dislodged material can be conveyed rearwardly by the conveyor mechanism on the mining machine to the discharge section 22.

A forwardly extending boom member generally designated by the numeral 26 has a pair of parallel rearwardly extending arm members 28 and 30 that are connected to each other adjacent the front end by means of a transverse housing 32. The arm members 28 and 30 are pivotally connected to the mining machine body portion 12 and are also pivotally connected at 34 to a piston rod 36 of the shear piston cylinder assembly 38. The shear piston cylinder assemblies 38 are, in turn, pivotally connected to the mining machine body portion 12 at 40. With this arrangement, extension and retraction of the piston rods 36 within the piston cylinder assemblies 38 pivot the boom member about the arm member rear end portions and move the boom member 26 vertically to the position illustrated in FIG. 2 for the upward shear cut by the drum. v

The boom member 26 has a second pair of parallel arm or support members 42 and 44 that are illustrated in greater detail in FIG. 4. The arms 42 and 44 are supported adjacent their rear end on stabilizer rods 46 and 48 that are secured to and extend laterally from the respective arm members 28 and 30 of boom 26. The stabilizer rods 46 and 48 are generally cylindrical passageways 50 in the respective arm members 42 and 44.

The housing 32 that supports the ends of arm members 28 and 30 in spaced parallel relation to each other on opposite sides of the conveyor 18 has a cylinder 52 therein (FIG. 4). Piston rods 54 and 56 are fixedly secured at one end to the arm members 42 and 44 and to pistons 58 within the cylinder 52. Suitable openings (not shown) are provided to supply hydraulic fluid under pressure to the cylinder 52 to exert a force onthe respective pistons 58 and move the arm members 42 and 44 laterally relative to the arm members 28 and 30 to either extend and retract a drum member generally designated by the numeral 60. Hydraulic drum rotating motors 62 and 64 are secured to the laterally movable arm members 42 and 44 for lateral movement therewith. The motors 62 and 64 are connected through clutch mechanisms 66 and planetary gear mechanism 68 to a gear train generally designated by the numeral 70 (FIG. 4) to the drum member 60 to rotate the drum member and dislodge material from the face.

FIGS. 4, and 6 illustrate in detail the drum member 60 and the drive means therefor. The drum member 60 hasa center section 72, a pair of intermediate sections 74 and 76, and a pair of end sections 78 and 80. The arm members 42 and 44 have forwardly extending end portions 82 with annular transverse sleeve or cylindrical portions 84 and 86. The arm members 42 and 44 have elongated chambers for housing the drive gear trains 70 with arcuate front end portions 88.

Since the mining machine is substantially symmetrical on opposite sides of the longitudinal axis, only one half of the drum member and drive train for that half will be described in detail. It should. be understood that the opposite portion of the-machine is identical. The drum member 60 has a generally tubular member 90 rotatably supported in the arm member sleeve portions 84 and 86 with bearings 92 and 94 positioned therebetween. The tubular member 90 is thus rotatably mounted within the sleeve members 84 and 86 and has a drive gear 96 nonrotatably secured to its outer periphery and extending into the-gear housing or the arm members 42 and 44 (see FIGS. 4, 5 and 6). The drive train 70 has other gears meshing with drive gear 96 to provide rotation for the tubular member 90 and the drum member 60;

The drum member end portions 78 have a generally;

cup-shaped configuration with V a central cylindrical passageway 98 with key or spline portions 100 therein.

The tubular member 90 has an end portion extending. into the central passageway 98 and has mating spline portions that nonrotatably connect the tubular member to the drum' member end portions 78. Bolts 102 secure the drum memberend portion 78 to the tubular member 90. With this arrangement, the drum member end portions 78 are connected to and rotate with the member90. A sprocket wheel 104 is connected to the inner annular end portion of the end section 78 adjacent to the arm member forwardly extending end portions 82. v

The drum member intermediate portions 74 and 76 have a generally cylindrical configuration with an outer annular end wall 106 and an inner annular end wall 108. A cylindrical inner member 110 is secured as by welding to the inner wall of the drum member intermediate portions 74 and 76 and has a splined inner wall 112 that mates with the splined outer wall of the tubular member 90 to nonrotatably connect the drum member intermediate portions 74 and 76 through the cylindrical inner member 110 to the member 90. Bolts 1 l4 secure the cylindrical inner member 1 10 to the end portion of member 90 for rotation therewith. With this construction, rotation of the member 90 is transmitted through the cylindrical inner member 110 to the intermediate sections 74 and 76. A sprocket 116 is secured to the annular end portion 106 of the drum member intermediate section 74 adjacent the end portions 82.

The drum member intermediate sections 74 and 76 have inner end walls 108 that are nonperpendicular to the longitudinal axis of the drum member. The end walls 108 are cut on a slant or bias relative to the longitudinal axis of the drum member intermediate portions 74 and 76. For example, the end wall 108 is at an angle of about 30 to a transverse axis of the drum member intermediate sections 74. It should be understood, however, that the angular relationship of the end walls of the intermediate and center sections of the drum member that face each other may be varied and thereby vary the dimension of overlapping as the sections are extended.

The drum member center section 72 has a generally cylindrical configuration with a pair of end walls 118 and 120. The end walls 118 and 120 are also cut on a bias or slant nonperpendicular to the longitudinal axis of the drum member. The angularity of the drum member center section end walls 118 and 120 is preferably the same as the angularity of the end walls 108 of the intermediate sections 74 and 76 so that upon retraction of the drum member 60, the respective adjacent end walls may be moved into abutting relation with each other.

The center section 72 is cylindrical in configuration and has an inner cylindrical member 122 positioned axially therein with an intermediate annular member 124 secured thereto as by welding. The outer wall of the intermediate member 124 is in turn secured to the inner wall of the center section 72 by similar welds. The inner cylindrical member 122 has an axial bore therethrough with a splined inner wall 126. A pair of shafts 128 are secured to the member 122 and extend outwardly therefrom. The shafts 128 have a splined end portion 130 that is positioned in the splined axial bore 126 of inner cylindrical member 122 to nonrotatably secure the shafts 128 within the drum center section 72. The

1 shafts 128 have annular. flanged shoulder portions 132 that are secured to the annular end wall 134 of inner cylindrical member 122 to nonrotatably secure the shafts 128 to the drug member center section 72. The shafts 128 have end portions 136 of reduced diameter with longitudinal splines thereon and the tubular member 90 has an annular inwardly extending splined connecting portion 138 through which the shaft end portion 136 extends and is nonrotatably secured therein. An end cap 140 secured to the end of the shaft 128 abuts the shoulder portion 142 of connecting portion 138 in the drum member extended position to limit the outward extension of the drum member 60.

The shaft member 128 is thus telescopically positioned within the connecting portion 90 to permit the intermediate and outer sections of the drum member to move outwardly away from the center section 72 and to maintain driving relationship therebetween by means of the shafts 128. Upon retraction, as illustrated in FIG. 6, the splined end portion 136 of shaft 128 moves axially within the member 90 to permit retraction of the intermediate and end portions of drum member 60 against the center portion 72 where the respective walls 108 of the intermediate portion abut the walls 118 and 120 ofthe center portion 72.

Cutter bits designated by the numeral 144 are secured to and extend angularly outwardly from the center, intermediate and end sections of the drug member 60 and are arranged so that, upon rotation of the drum member 60, the cutter bits dislodge material from the face. The cutter bits 144 are preferably so positioned on the respective sections of the drum that during rotation substantially the entire mine face along the entire length of the drum member 60 at the line of tangency between the drum member and the face is subjected to the dislodging action of the bits 144. The stationary front end portions 82 of arm members 42 and 44 have pairs of endless cutter chains reeved about sprockets 104 and 116 and idler sprockets 146 rotatably supported on the respective arm members 42 and 44 by means of shaft 148 as illustrated in FIG. 4. The endless cutter chains have cutter bits secured thereto at divergent angles to dislodge the material between the end cutter bits on the intermediate and end drum sections. The chains are driven at the same peripheral speed as the drum sections by the sprockets 104 and 116 on the sections. The shafts 128 extend outwardly from the drum member section 72 and the members 90 rotatably supported in the annular transverse sleeve portions 84 and 86 of the gear housing 88 form a unitary telescopic shaft connecting all of the sections of the drum member 60 so that the drum member 60 rotates as a single unit.

In FIG. 4 the drive gear train 70 for the drum member 60 is illustrated in detail. Each drive motor 62 and 64 has a drive shaft 148 that extends through gear housing 88 to a clutch mechanism 150. The driven member of the clutch mechanism 150 is connected to a coaxial tubular shaft 152 that is, in turn, drivingly connected to a planetary gear assembly 154, the planet gears of which are connected through a bracket 156 to a first gear 158 of the gear train 70 within the chamber in the arm members. The gear 158 is connected to drive gear 96 through an idler gear 160. Drive motor rotation is transmitted through the drive shaft 148 to a clutch mechanism 150 and from the clutch mechanism 150 through a planetary gear train 154 to a gear 158 of the drive gear train 70. Gear 158 is connected through idler gear 160 to the drive gear 96 nonrotatably secured to member 90 which, in turn, in nonrotatably secured to the three sections of the drum 60.

The endless cutter chains 162 and 164 reeved about the respective sprockets 146 and sprockets 104 and 116 are driven by the outer and intermediate drum member sections at the same angular velocity as the drum member 60 by the same drive train and have cutter bits so positioned thereon to dislodge the kerf of material in front of the stationary portion of arms 42 and 44 so that the entire face along the length of the drum either in an extended or retracted position is subjected to a dislodging action of the cutter bits on the drum 60. To dislodge material from the face, it is preferred to advance the mining machine into the face with the drum member 60 rotating and in a lower position, as illustrated in full lines in FIG. 2. The shear cylinder assemblies 38 then pivot the boom member 26 and move the drum member 60 upwardly along the path illustrated in phantom lines in FIG. 2 to dislodge material from the face across the entire face as the drum is raised to the upper illustrated position.

With the above described arrangement is is now possible to extend the cutter drum 60 to a dimension substantially wider than the mining machine and maintain the cutting pattern of the bits on all sections of the extended drum in a generally overlapping relation to dislodge material along the entire length of the drum. To retract the drum 60 for tramming and maneuvering the mining machine within the entry, the pistons 58 in cylinder 52 are subjected to hydraulic fluid under pressure to move the arm members 42 and 44 inwardly toward the center of the machine and retract the drug sections on the shafts and thereby reduce the longitudinal dimension of the drum from that illustrated in FIGS. 1 and 4 to that illustrated in FIGS. 3 and 6. Although the angularly formed end walls of the drum center section 72 and the intermediate sections 74 and 76 are arranged in parallel relation to each other in the illustrated embodiment, it should be understood that the angularity of the respective walls may deviate from a parallel relationship as long as the cutter bits on the center section and intermediate sections overlap in an extended position to prevent the formation of upstanding kerfs in the face.

Referring to FIG. 7, another embodiment of an extendible drum suitable for use on the mining machine 10 is illustrated. The drum generally designated by the numeral 166 has a center section 168 and a pair of intermediate sections 170 and 172. The end sections of the drum are similar to the end sections of drum 60 previously described. The center section 168 has a plurality of end recessed portions 174 with outwardly extending portions 176 therebetween. The intermediate sections have similar recessed portions 178 with inwardly extending portions 180 therebetween. The configuration of the recessed portions and portions therebetween on both the center section 168 and intermediate sections 170 and 172 are so dimensioned that the extending portions of the adjacent members fit into the recessed portions of the adjacent members when the drum 166 is in a retracted or tram position. Cutter bits are positioned on the extending portions 176 and 180 to provide for full face bit patterns when the drum 166 is in the extended position illustrated in FIG. 7.

Referring now to the embodiment illustrated in FIGS. 8, 9 and 10, there is illustrated a continuous mining machine generally designated by the numeral 210 that has a substantial number of elements similar to the mining machine previously described in reference to FIGS. 1 and 2. The mining machine 210 has a frame portion 212 suitably mounted on endless crawler tracks 214. Hydraulic drive motors 216 are provided to propel the mining machine 210 in a similar manner as previously described. The mining machine illustrated in FIGS. 8, 9 and 10 also includes an endless conveyor mechanism 218 positioned in a longitudinal trough 220 to convey the dislodged material from the front end of the mining machine 210 to an articulated rear discharge section 222. A gathering device 224 extends forwardly from the body portion 212 and gathers and feeds the dislodged material onto the conveyor trough 220. A forwardly extending boom assembly generally designated by the numeral 226 has a pair of rearwardly extending arm members 228 and 230 that are connected to each other by a transverse portion 232. The arm members 228 and 230 are pivotally connected to the mining machine body portion 212 and are also pivotally connected at 234 to a piston rod 236 of the shear piston assembly 238. The pair of shear piston assemblies 238 are in turn pivotally connected to the mining machine body portion 212 at 240. With this arrangement, as previously described in reference to FIGS. 1 and 2, extension and retraction of the piston rods 236 within the piston cylinder assemblies 238 pivot the boom member about the arm member rear end portions and move the boom member 226 vertically to the position illustrated in FIG. 10 in dash-dot lines for the upward shear cut by the drum member.

The boom member assembly 226 has a second pair of parallel arms 242 and 244 that extend forwardly from the transverse portion 232. A pair of piston cylinder assemblies 246 and 248 are secured to the front ends of the respective forwardly extending arms 242 and 244. Positioned inwardly of the arm members 242 and 244 on the boom assembly 226 are a pair of drum support arms 250 and 252. The drug support arms 250 and 252 have their rear end portions 254 and 256 slidably positioned in a recessed portion 258 in the boom assembly transverse portion 232 so that the drum support arm members 250 and 252 are slidable toward and away from each other. TI-Ie respective drum support arm members 250 and 252 have an outer plate 260 and an inner plate 262 that are connected to each other adjacent their rear portions 254 or 256 and enclose a gear housing 264 that is similar to the gear housing for the drive gearing, as illustrated in FIG. 4.

The piston cylinder assemblies 246 and 248 have piston rods 266 and 268 extending therefrom and secured to the plates 260 of the drug support arms 250 and 252. The piston rods 266 and 268 are arranged to slidably move the drum support arms 250 and 252 toward and away from each other. Drive motors 270 and 272 are mounted on the drum support arms 250 and 252 outboard of the plates 260 and adjacent to the respective piston cylinder assemblies 246 and 248. The drive motors 270 and 272 are arranged to drive the gearing within the housing 264 to rotate the drum member generally designated by the numeral 274.

The gear housing 264 rotatably supports the drum member 274 therein in a manner similar to that illustrated in FIGS. 1 and 4 so that the motors 270 and 272 through the drive gearing within housings 264 rotate the drum member 274.

The drum member 274 has a pair of end sections 276 and 278 and a pair of intermediate sections 280 and 282. The end sections 276 and 278 and intermediate sections 280 and 282 are similar to the end and intermediate sections of the drum member illustrated in FIG. 4. A shaft 284 is telescopically positioned within the intermediate sections 280 and 282 so that the intermediate sections 280 and 282 may move toward and away from each other, as illustrated in FIGS. 8 and 9, while supported on shaft 284.

The drum member end sections 276 and 278 are similar to the drum member end sections 78 and 80 illustrated in FIG. 4. The intermediate sections 280 and 282 have inner end walls 286 and 288 that extend in nonparallel relation to the longitudinal axis of the drum member 274 and are arranged substantially parallel to each other. As previously discussed, in an extended position the cutter bits 290 on the intermediate sections 280 and 282 overlap in both a retracted and extended position so that in an extended position the drum member 274 dislodges material along the entire length of the drum member 274. Endless chains 292 are mounted on the exterior portion of housing 264 to dislodge the material between the drum member end sections 276, 278 and intermediate sections 280 and 282. A fragmentary portion of the chains 292 are illustrated in FIG. 8 and are omitted from FIG. 9 to better illustrate the other elements of the mining machine 210. It should be understood that the arrangement of chains 292 is similar to that illustrated in FIGS. 1 and 4. Other means may also be provided to dislodge the material between the adjacent end and intermediate section of the drum member.

With the above arrangement the drum member 274 is provided with a pair of end sections 276 and 278 and a pair of inboard intermediate sections 280 and 282. In the embodiment illustrated in FIGS. 8, 9 and 10, the center section as previously described in reference to FIGS. 1 and 3 is omitted and the drum member 274 dislodges material along the entire length thereof. The piston cylinder assemblies 246 and 248 are arranged to move the drug support arms 250 and'252 toward and away from each other to thus increase and decrease the length of the drum member 274. The drive motors 270 and 272 are positioned on the outboard side of the drum support arms 250 and 252 to provide additional room for the gathering of the dislodged material by the gathering device 224. The drum support arms 250 and 252 are suitably supported by the boom assembly forwardly extending arms 242 and 244.

According to the provisions of the patent statutes, I have explained the principle, preferred construction and mode of operation of my invention and have illustrated and described what I now consider to represent its best embodiments. However, it should be understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically illustrated and described.

lclaim:

l. A continuous mining machine comprising,

an elongated body portion mounted on propelling means,

a boom member pivotally secured to said body portion and extending forwardly therefrom,

a drum member rotatably mounted on the front of said boom member transversely to said body portion,

said drum member having a plurality of aligned sections,

means nonrotatably connecting said sections to each other,

means to move said sections outwardly away from each other to an extended position and thereby increase the length ofsaid drum member, and

certain of said drum member sections having adjacent walls nonperpendicular to said drum member longitudinal axis so that said sections are operable to maintain a continuous longitudinal cutting pattern along the length of said drum member when said drum member is in an extended position.

2. A continuous mining machine as set forth in claim 1 in which, I

said drum member includes a center section and a pair of end sections, and

means to move said end sections outwardly away from said center section to an extended position and thereby increase the length of said drum member.

3. A continuous mining machine as set forth in claim 2 in which,

said means nonrotatably connecting said sections to each other includes,

a pair of shaft members nonrotatably secured to said center section and extending transversely therefrom,

said end sections having axial passageways therethrough,

said shaft members nonrotatably positioned in said passageways and telescopically movable therein to extend and retract said end sections from said center section. 4. A continuous mining machine as set forth in claim 2 in which,

said end sections each have inner end walls nonperpendicular to the longitudinal axis of said drug member, and said center section having end walls nonperpcndicular to said drum member longitudinal axis. 5. A continuous mining machine as set forth in claim 4 in which,

said center section end walls and said adjacent end section end walls arranged substantially parallel to each other. 6. A continuous mining machine as set forth in claim I in which,

certain of said drum member sections having inner end walls nonperpendicular to the longitudinal axis ofsaid drum member, and said inner end walls arranged substantially parallel to each other. 7. A continuous mining machine as set forth in claim 1 in which.

said boom member has a pair of spaced arm members secured to said drum member end sections, and

means to move said arm members toward and away from each other to thereby extend and retract said drum member. 8. A continuous mining machine as set forth in claim 5 7in which,

said means to move said arm members toward and away from each other includes,

a pair of stabilizer rods extending laterally in opposite directions from said boom member,

said boom member having a transversely extending cylinder positioned forwardly of said stabilizer rod,

a pair of pistons positioned in said cylinder and each piston having a piston rod extending therefrom and secured to one of said arm members,

said arm members having transverse passageways therethrough adjacent their end portions, and

said stabilizer rods extending through said passageways and said pistons operable to move said arms laterally toward and away from each other.

9. A continuous mining machine as set forth in claim 1 which includes,

motor means mounted on said boom member and said boom member includes a pair of arm members extending forwardly therefrom in spaced parallel relation,

a pair of drum support members arranged in parallel spaced relation and secured to said arm members, said drug support members rotatably supporting said drum member thereon, and

means to move said drum support members toward and away from each other to thereby increase and decrease the length of said drum member. 11. A continuous mining machine as set forth in claim 10 in which,

said means to move said drum support members toward and away from each other includes transversely extending cylinders secured to the front end portions of said boom arm mem bers, and a piston positioned in each of said cylinders and having a piston rod extending therefrom and secured to one of said drum'support members. 12. A continuous mining machine as set forth in claim 11 in which,

said boom member includes a transverse base portion with said arm members extending forwardly therefrom, and

said transverse base portion including means to slidably support the rear edge portion of said support member. 13. A continuous mining machine as set forth in claim 1 in which,

said means nonrotatably connecting said sections to each other includes a shaft member nonrotatably secured to said sections and telescopically movable therein to permit movement of said sections toward and away frog each other. 14. A continuous mining machine as set forth in claim 1 in which,

said drum member includes a pair of intermediate sections positioned between said end sections and said center section,

said end sections and said intermediate sections having aligned axial passageways therein,

a tubular member nonrotatably secured in each of said adjacent end and intermediate sections,

a pair of shaft members nonrotatably secured to said center section and extending transversely therefrom,

said shaft members nonrotatably positioned in said tubular member and telescopically movable therein to'extend and retract said end sections from said center section.

15. A continuous mining machine as set forth in claim 14 in which,

said boom member has a pair of spaced arm members extending forwardly therefrom,

said arm members having a housing with a transverse tubular portion adjacent the arm member end portions and a rearwardly extending portion communicating with said transverse tubular portion,

said tubular member rotatably supported in said transverse tubular portion, and

drive gearing in said housing drivingly connected to said tubular member.

16. A continuous mining machine as set forth in claim 1 in which,

said boom member has a pair of spaced forwardly extending drum support members, said drum support members having a housing with a transverse tubular portion adjacent said drum support member from end portion and a rearwardly extending portion communicating with said transverse tubular portion, and drive gearing in said housing drivingly connected to said drum member within said housing. i 17. A continuous mining machine as set forth in claim 15 which includes,

drive motors supported on and movable with said drum support members, said drive motors drivingly connected to said drive gearing in said housing. 18. A continuous mining machine as set forth in claim 1 in which,

said center section includes a plurality of longitudinally extending end recessed portions and a plurality of outwardly extending portions therebetween, said end sections having a plurality of longitudinally extending end recessed portions and outwardly extending portions therebetween. 

1. A continuous mining machine comprising, an elongated body portion mounted on propelling means, a boom member pivotally secured to said body portion and extending forwardly therefrom, a drum member rotatably mounted on the front of said boom member transversely to said body portion, said drum member having a plurality of aligned sections, means nonrotatably connecting said sections to each other, means to move said sections outwardly away from each other to an extended position and thereby increase the length of said drum member, and certain of said drum member sections having adjacent walls nonperpendicular to said drum member longitudinal axis so that said sections are operable to maintain a continuous longitudinal cutting pattern along the length of said drum member when said drum member is in an extended position.
 2. A continuous mining machine as set forth in claim 1 in which, said drum member includes a center section and a pair of end sections, and means to move said end sections outwardly away from said center section to an extended position and thereby increase the length of said drum member.
 3. A continuous mining machine as set forth in claim 2 in which, said means nonrotatably connecting said sections to each other includes, a pair of shaft members nonrotatably secured to said center section and extending transversely therefrom, said end sections having axial passageways therethrough, said shaft members nonrotatably positioned in said passageways and telescopically movable therein to extend and retract said end sections from said center section.
 4. A continuous mining machine as set forth in claim 2 in which, said end sections each have inner end walls nonperpendicular to the longitudinal axis of said drug member, and said center section having end walls nonperpendicular to said drum member longitudinal axis.
 5. A continuous mining machine as set forth in claim 4 in which, said center section end walls and said adjacent end section end walls arranged substantially parallel to each other.
 6. A continuous mining machine as set forth in claim 1 in which, certain of said drum member sections having inner end walls nonperpendicular to the longitudinal axis of said drum member, and said inner end walls arranged substantially parallel to each other.
 7. A continuous mining machine as set forth in claim 1 in which, said boom member has a pair of spaced arm members secured to said drum member end sections, and means to move said arm members toward and away from each other to thereby extend and retract said drum member.
 8. A continuous mining machine as set forth in claim 7 in which, said means to move said arm members toward and away from each other incluDes, a pair of stabilizer rods extending laterally in opposite directions from said boom member, said boom member having a transversely extending cylinder positioned forwardly of said stabilizer rod, a pair of pistons positioned in said cylinder and each piston having a piston rod extending therefrom and secured to one of said arm members, said arm members having transverse passageways therethrough adjacent their end portions, and said stabilizer rods extending through said passageways and said pistons operable to move said arms laterally toward and away from each other.
 9. A continuous mining machine as set forth in claim 1 which includes, motor means mounted on said boom member and movable therewith, and gearing connecting said motor means to said drum member for rotating said drum member on said boom member.
 10. A continuous mining machine as set forth in claim 1 in which, said boom member includes a pair of arm members extending forwardly therefrom in spaced parallel relation, a pair of drum support members arranged in parallel spaced relation and secured to said arm members, said drug support members rotatably supporting said drum member thereon, and means to move said drum support members toward and away from each other to thereby increase and decrease the length of said drum member.
 11. A continuous mining machine as set forth in claim 10 in which, said means to move said drum support members toward and away from each other includes transversely extending cylinders secured to the front end portions of said boom arm members, and a piston positioned in each of said cylinders and having a piston rod extending therefrom and secured to one of said drum support members.
 12. A continuous mining machine as set forth in claim 11 in which, said boom member includes a transverse base portion with said arm members extending forwardly therefrom, and said transverse base portion including means to slidably support the rear edge portion of said support member.
 13. A continuous mining machine as set forth in claim 1 in which, said means nonrotatably connecting said sections to each other includes a shaft member nonrotatably secured to said sections and telescopically movable therein to permit movement of said sections toward and away frog each other.
 14. A continuous mining machine as set forth in claim 1 in which, said drum member includes a pair of intermediate sections positioned between said end sections and said center section, said end sections and said intermediate sections having aligned axial passageways therein, a tubular member nonrotatably secured in each of said adjacent end and intermediate sections, a pair of shaft members nonrotatably secured to said center section and extending transversely therefrom, said shaft members nonrotatably positioned in said tubular member and telescopically movable therein to extend and retract said end sections from said center section.
 15. A continuous mining machine as set forth in claim 14 in which, said boom member has a pair of spaced arm members extending forwardly therefrom, said arm members having a housing with a transverse tubular portion adjacent the arm member end portions and a rearwardly extending portion communicating with said transverse tubular portion, said tubular member rotatably supported in said transverse tubular portion, and drive gearing in said housing drivingly connected to said tubular member.
 16. A continuous mining machine as set forth in claim 1 in which, said boom member has a pair of spaced forwardly extending drum support members, said drum support members having a housing with a transverse tubular portion adjacent said drum support member front end portion and a rearwardly extending portion communicating with said transverse tubular portion, and drive gearing in said housing drivingly connected to said drum member within said housing.
 17. A continuous mining machine as set forth in claim 15 which includes, drive motors supported on and movable with said drum support members, said drive motors drivingly connected to said drive gearing in said housing.
 18. A continuous mining machine as set forth in claim 1 in which, said center section includes a plurality of longitudinally extending end recessed portions and a plurality of outwardly extending portions therebetween, said end sections having a plurality of longitudinally extending end recessed portions and outwardly extending portions therebetween. 